No abstract

Background Aging is often associated with behavioral impairments, but some people age more gracefully than others. Why? One factor that may play a role is individual differences in the distinctiveness of neural representations. Previous research has found that neural activation patterns in visual cortex in response to different visual stimuli are often more similar (i.e., less distinctive) in older vs. young participants, a phenomenon referred to as age-related neural dedifferentiation. Furthermore, older people whose neural representations are less distinctive tend to perform worse on a wide range of behavioral tasks. The Michigan Neural Distinctiveness (MiND) project aims to investigate the scope of neural dedifferentiation (e.g., does it also occur in auditory, motor, and somatosensory cortex?), one potential cause (age-related reductions in the inhibitory neurotransmitter gamma-aminobutyric acid (GABA)), and the behavioral consequences of neural dedifferentiation. This protocol paper describes the study rationale and methods being used in complete detail, but not the results (data collection is currently underway). Methods The MiND project consists of two studies: the main study and a drug study. In the main study, we are recruiting 60 young and 100 older adults to perform behavioral tasks that measure sensory and cognitive function. They also participate in functional MRI (fMRI), MR spectroscopy, and diffusion weighted imaging sessions, providing data on neural distinctiveness and GABA concentrations. In the drug study, we are recruiting 25 young and 25 older adults to compare neural distinctiveness, measured with fMRI, after participants take a placebo or a benzodiazepine (lorazepam) that should increase GABA activity. Discussion By collecting multimodal imaging measures along with extensive behavioral measures from the same subjects, we are linking individual differences in neurochemistry, neural representation, and behavioral performance, rather than focusing solely on group differences between young and old participants. Our findings have the potential to inform new interventions for age-related declines. Trial registration This study was retrospectively registered with the ISRCTN registry on March 4, 2019. The registration number is ISRCTN17266136 .

1 Background: Aging is often associated with behavioral impairments, but some people age more 2 gracefully than others. Why? One factor that may play a role is individual differences in the 3 distinctiveness of neural representations. Previous research has found that neural activation 4 patterns in visual cortex in response to different visual stimuli are often more similar (i.e., less 5 distinctive) in older vs. young participants, a phenomenon referred to as age-related neural 6 dedifferentiation. Furthermore, older people whose neural representations are less distinctive 7 tend to perform worse on a wide range of behavioral tasks. The Michigan Neural Distinctiveness 8 (MiND) project aims to investigate the scope of neural dedifferentiation (e.g., does it also occur 9 in auditory, motor, and somatosensory cortex?), one potential cause (age-related reductions in 10 the inhibitory neurotransmitter gamma-aminobutyric acid (GABA)), and the behavioral 11 consequences of neural dedifferentiation. This protocol paper describes the study rationale and 12 methods being used in complete detail, but not the results (data collection is currently underway). 13Methods/Design: The MiND project consists of two studies: the main study and a drug study. In 14 the main study, we are recruiting 60 young and 100 older adults to perform behavioral tasks that 15 measure sensory and cognitive function. They also participate in functional MRI (fMRI), MR 16 spectroscopy (MRS), and diffusion weighted imaging (DWI) sessions, providing data on neural 17 distinctiveness and GABA concentrations. In the drug study, we are recruiting 25 young and 25 18 older adults to compare neural distinctiveness, measured with fMRI, after participants take (1) a 19 benzodiazepine (lorazepam) that should increase GABA activity or (2) a placebo. 20 Discussion: By collecting multimodal imaging measures (fMRI, MRS, DWI) along with 21 extensive behavioral measures from the same subjects, we are linking individual differences in 22 neurochemistry, neural representation, and behavioral performance, rather than focusing solely 23 3 on group differences between young and old participants. Our findings have the potential to 24 inform new interventions for age-related declines. 25 Background 29Normal aging is associated with pervasive declines in cognitive, motor, and sensory 30 function, even in the absence of significant disease. Further, both the number of older adults and 31 the proportion of older adults in the population are growing at alarming rates. Consequently, tens 32 of millions of healthy people are already experiencing age-related behavioral impairments, and 33 that number is only going to grow. Nevertheless, there are substantial individual differences in 34 age-related behavioral impairments. Some otherwise healthy people experience significant age-35 related declines, while others do not. What distinguishes those who age gracefully from those 36 who experience significant impairments? The answer to that question could transform efforts to 37 reduce, o...

By magnifying gender‐ and socioeconomic status‐based inequalities, the COVID‐19 pandemic caused stress and disrupted career progress for professional students. The present work investigated the impact of pandemic‐related stress and prevailing barriers on structurally disadvantaged women preparing for a high‐stakes professional exam. In Study 1, we found that among US law students preparing for the October 2020 California Bar Exam—the professional exam that enables one to become a practicing attorney in California—first‐generation women reported the greatest stress from pandemic‐related burdens and underperformed on the exam relative to others overall, and particularly compared to continuing‐generation women. This underperformance was explained by pandemic‐related stress they contended with most, as well as by structural demands shouldered most by first‐generation test‐takers regardless of gender. Even when controlling for the structural features of caregiving and working while studying, the psychological burdens experienced most by first‐generation women predicted lower exam success. Study 2 investigated the February 2021 California Bar Exam. Consistent with Study 1, first‐generation women test‐takers reported the most pandemic‐related stress, which predicted lower exam performance above and beyond structural barriers to exam success. We offer policy prescriptions to bolster the success of at‐risk groups in the legal profession pipeline, a challenge magnified by the pandemic.

No abstract